In recent days, Google accused Bing of copying its search results, which has set off yet another Microsoft versus Google debate.

Bing executive Yusuf Mehdi, senior vice president of Microsoft’s Online Services Division, blogged about the accusation, remarking that, “We do not copy results from any of our competitors. Period. Full stop.” In the same blog, he accused Google of a “cloak and dagger click fraud” scheme to discredit Bing’s search practices.

And what of this ‘click fraud'; an attack employed by spammers on the web to trick consumers and produce bogus search results? Earlier this week, Search Engine Land wrote about a Google experiment that ended up showing Bing’s results for a few obscure queries mirror those of Google’s. Microsoft, shocked into going on the defensive, said it uses tools that monitor the search practices of users who opt in anonymously. That process happened to cause some Bing results to apparently mimic Google’s, Microsoft said.

Mehdi described Google’s “experiment” as rigged to manipulate Bing search results through said click fraud.

So, what does this prove? As stated succinctly at the Microsoft blog, “Nothing anyone in the industry doesn’t already know. As we have said before and again in this post, we use click stream optionally provided by consumers in an anonymous fashion as one of 1,000 signals to try and determine whether a site might make sense to be in our index.”